The St. Louis Cardinals welcome the Arizona Diamondbacks to Busch Stadium on Tuesday, June 23, 2026, for a 7:45 PM ET first pitch. Kyle Leahy gets the ball for St. Louis against veteran lefty Eduardo Rodriguez, and with a lineup that blends emerging young talent and proven contributors, this is a game the Cardinals need to take seriously. Every rep matters as the summer stretch run approaches, and home games at Busch Stadium are opportunities to build momentum that carries into the weeks ahead.

Cardinals vs. Diamondbacks Starting Pitchers: Leahy vs. Rodriguez

Kyle Leahy draws the start for St. Louis, and this is a meaningful opportunity for the young arm to show what he can bring to this rotation. Leahy has the stuff to keep hitters off balance, but the command and consistency he demonstrates against a disciplined Arizona lineup will tell you a lot about where he stands heading into the second half of the season. The Diamondbacks are not a team that gives away at-bats, so Leahy will need to be sharp from pitch one.

Eduardo Rodriguez brings experience to the mound for Arizona. The left-hander has logged significant big-league innings and knows how to navigate a lineup. The Cardinals will need to be aggressive early in counts and avoid falling into predictable at-bats against a pitcher who thrives when hitters are passive.

St. Louis Cardinals Starting Lineup for June 23

• 1. JJ Wetherholt, 2B
• 2. Iván Herrera, DH
• 3. Nelson Velázquez, LF
• 4. Jordan Walker, RF
• 5. José Fermín, 3B
• 6. Masyn Winn, SS
• 7. Lars Nootbaar, CF
• 8. Blaze Jordan, 1B
• 9. Pedro Pagés, C

JJ Wetherholt leads off and his ability to work the count and get on base sets the table for everything that follows. Iván Herrera batting second in the DH spot is an interesting wrinkle — the Cardinals are clearly looking to keep his bat in a high-leverage spot in the order. Jordan Walker hitting cleanup is the right call. His power potential against a left-handed starter like Rodriguez is a genuine matchup advantage the Cardinals should be able to exploit.

Keys to Watch Against Arizona

Jordan Walker vs. Eduardo Rodriguez

Walker versus a left-handed starter is a matchup St. Louis has to win. If Walker can do damage in his first two at-bats against Rodriguez, it changes the entire complexion of the game and puts pressure on the Arizona bullpen early.

Masyn Winn Providing Lineup Depth

Winn hitting sixth keeps the Cardinals dangerous deep in the order. His ability to make contact and put pressure on the defense with his legs means Arizona cannot simply cruise through the bottom of this lineup.

Leahy's Command in Early Innings

If Leahy falls behind in counts and starts battling from two-strike situations, the Diamondbacks have the lineup to make him pay. The Cardinals need three to four clean innings out of their starter before they can lean on the bullpen with confidence.

Prediction

The Cardinals take this one at home. Walker does damage against Rodriguez, Wetherholt sets the table at the top, and Leahy gives St. Louis enough innings to keep it a manageable game for the bullpen. Busch Stadium crowd gets a win. Cardinals 5, Diamondbacks 3.

Catch the game on KMOX 1120 AM and Cardinals.TV Presented by bet365. First pitch is set for 7:45 PM ET.